From nobody Thu Apr 2 19:15:32 2026 Received: from mail.ilvokhin.com (mail.ilvokhin.com [178.62.254.231]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F346D44BCA8; Fri, 27 Feb 2026 16:01:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.62.254.231 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772208086; cv=none; b=cKSwX/4DgdaDHWDPs8rkGPRIvKlJyRA5wt/JPCdA3/Gvm7a/13LwP+3q9rIPgGUQ7v0/h3o9TQDPpCkOGuIztPDegeOH84ZqppXvHM3PXxA0X9C6GHAQZ9r/sAnn7vIsgZcd1vwc1GjhxD1oLnWeaQezzqVa1dpGMIOWxRcwf1I= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772208086; c=relaxed/simple; bh=KEsXHJwZo50cCT5cstGo00W1cHACMATdZTFoqQfY1RU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=EXhX4ggS5DBwXtKspXU2nZb5jp0Mfy/1z3GsI23b/gcOctbF+tultVszbXbDYTaVMbBaxQBPF094BWP1pSTpckbAg1wR1WRPW434B/25IcEKHVP1/SH2EbQvisFxpFjotOhxLQFFmBj/r+PmeLzq+QsH+B+JPglsAxUpSItXaao= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ilvokhin.com; spf=pass smtp.mailfrom=ilvokhin.com; dkim=pass (1024-bit key) header.d=ilvokhin.com header.i=@ilvokhin.com header.b=OmCP9/DM; arc=none smtp.client-ip=178.62.254.231 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=ilvokhin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ilvokhin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ilvokhin.com header.i=@ilvokhin.com header.b="OmCP9/DM" Received: from localhost.localdomain (shell.ilvokhin.com [138.68.190.75]) (Authenticated sender: d@ilvokhin.com) by mail.ilvokhin.com (Postfix) with ESMTPSA id 86B4BB2E42; Fri, 27 Feb 2026 16:01:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ilvokhin.com; s=mail; t=1772208074; bh=H/C6nJmlvrDB0ueIgBJj0PZ61C1YT1IHYyYUu5jqK3s=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=OmCP9/DMxndr53NYYC6Aez7arsnd5VK3fq19k00s/VgoEQIermd5lLGBYrfUIK8ry Ay3/yv03kXueNBBmdxDmF6/ktsx/b/kLHBjtfuIOf7a8tJpE2T7cXF6EuEmTtzouNi iJz51x894YOU4yv+YxPPsdQt5oXU3F7WArgkRhaA= From: Dmitry Ilvokhin To: Andrew Morton , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Axel Rasmussen , Yuanchu Xie , Wei Xu , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , "Rafael J. Wysocki" , Pavel Machek , Len Brown , Brendan Jackman , Johannes Weiner , Zi Yan , Oscar Salvador , Qi Zheng , Shakeel Butt Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, linux-pm@vger.kernel.org, "linux-cxl@vger.kernel.orgkernel-team"@meta.com, Dmitry Ilvokhin , SeongJae Park Subject: [PATCH v4 4/5] mm: rename zone->lock to zone->_lock Date: Fri, 27 Feb 2026 16:00:26 +0000 Message-ID: X-Mailer: git-send-email 2.53.0 In-Reply-To: References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" This intentionally breaks direct users of zone->lock at compile time so all call sites are converted to the zone lock wrappers. Without the rename, present and future out-of-tree code could continue using spin_lock(&zone->lock) and bypass the wrappers and tracing infrastructure. No functional change intended. Suggested-by: Andrew Morton Signed-off-by: Dmitry Ilvokhin Acked-by: Shakeel Butt Acked-by: SeongJae Park Acked-by: David Hildenbrand (Arm) Acked-by: Vlastimil Babka (SUSE) Acked-by: Zi Yan Reviewed-by: Vlastimil Babka (SUSE) --- include/linux/mmzone.h | 7 +++++-- include/linux/mmzone_lock.h | 12 ++++++------ mm/compaction.c | 4 ++-- mm/internal.h | 2 +- mm/page_alloc.c | 16 ++++++++-------- mm/page_isolation.c | 4 ++-- mm/page_owner.c | 2 +- 7 files changed, 25 insertions(+), 22 deletions(-) diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h index 3e51190a55e4..32bca655fce5 100644 --- a/include/linux/mmzone.h +++ b/include/linux/mmzone.h @@ -1009,8 +1009,11 @@ struct zone { /* zone flags, see below */ unsigned long flags; =20 - /* Primarily protects free_area */ - spinlock_t lock; + /* + * Primarily protects free_area. Should be accessed via zone_lock_* + * helpers. + */ + spinlock_t _lock; =20 /* Pages to be freed when next trylock succeeds */ struct llist_head trylock_free_pages; diff --git a/include/linux/mmzone_lock.h b/include/linux/mmzone_lock.h index a1cfba8408d6..62e34d500078 100644 --- a/include/linux/mmzone_lock.h +++ b/include/linux/mmzone_lock.h @@ -7,32 +7,32 @@ =20 static inline void zone_lock_init(struct zone *zone) { - spin_lock_init(&zone->lock); + spin_lock_init(&zone->_lock); } =20 #define zone_lock_irqsave(zone, flags) \ do { \ - spin_lock_irqsave(&(zone)->lock, flags); \ + spin_lock_irqsave(&(zone)->_lock, flags); \ } while (0) =20 #define zone_trylock_irqsave(zone, flags) \ ({ \ - spin_trylock_irqsave(&(zone)->lock, flags); \ + spin_trylock_irqsave(&(zone)->_lock, flags); \ }) =20 static inline void zone_unlock_irqrestore(struct zone *zone, unsigned long= flags) { - spin_unlock_irqrestore(&zone->lock, flags); + spin_unlock_irqrestore(&zone->_lock, flags); } =20 static inline void zone_lock_irq(struct zone *zone) { - spin_lock_irq(&zone->lock); + spin_lock_irq(&zone->_lock); } =20 static inline void zone_unlock_irq(struct zone *zone) { - spin_unlock_irq(&zone->lock); + spin_unlock_irq(&zone->_lock); } =20 #endif /* _LINUX_MMZONE_LOCK_H */ diff --git a/mm/compaction.c b/mm/compaction.c index c68fcc416fc7..ac2a259518b1 100644 --- a/mm/compaction.c +++ b/mm/compaction.c @@ -506,7 +506,7 @@ static bool test_and_set_skip(struct compact_control *c= c, struct page *page) static bool compact_zone_lock_irqsave(struct zone *zone, unsigned long *flags, struct compact_control *cc) - __acquires(&zone->lock) + __acquires(&zone->_lock) { /* Track if the lock is contended in async mode */ if (cc->mode =3D=3D MIGRATE_ASYNC && !cc->contended) { @@ -1402,7 +1402,7 @@ static bool suitable_migration_target(struct compact_= control *cc, int order =3D cc->order > 0 ? cc->order : pageblock_order; =20 /* - * We are checking page_order without zone->lock taken. But + * We are checking page_order without zone->_lock taken. But * the only small danger is that we skip a potentially suitable * pageblock, so it's not worth to check order for valid range. */ diff --git a/mm/internal.h b/mm/internal.h index cb0af847d7d9..6cb06e21ce15 100644 --- a/mm/internal.h +++ b/mm/internal.h @@ -710,7 +710,7 @@ static inline unsigned int buddy_order(struct page *pag= e) * (d) a page and its buddy are in the same zone. * * For recording whether a page is in the buddy system, we set PageBuddy. - * Setting, clearing, and testing PageBuddy is serialized by zone->lock. + * Setting, clearing, and testing PageBuddy is serialized by zone->_lock. * * For recording page's order, we use page_private(page). */ diff --git a/mm/page_alloc.c b/mm/page_alloc.c index bcc3fe0368fc..0d078aef8ed6 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -815,7 +815,7 @@ compaction_capture(struct capture_control *capc, struct= page *page, static inline void account_freepages(struct zone *zone, int nr_pages, int migratetype) { - lockdep_assert_held(&zone->lock); + lockdep_assert_held(&zone->_lock); =20 if (is_migrate_isolate(migratetype)) return; @@ -2473,7 +2473,7 @@ enum rmqueue_mode { =20 /* * Do the hard work of removing an element from the buddy allocator. - * Call me with the zone->lock already held. + * Call me with the zone->_lock already held. */ static __always_inline struct page * __rmqueue(struct zone *zone, unsigned int order, int migratetype, @@ -2501,7 +2501,7 @@ __rmqueue(struct zone *zone, unsigned int order, int = migratetype, * fallbacks modes with increasing levels of fragmentation risk. * * The fallback logic is expensive and rmqueue_bulk() calls in - * a loop with the zone->lock held, meaning the freelists are + * a loop with the zone->_lock held, meaning the freelists are * not subject to any outside changes. Remember in *mode where * we found pay dirt, to save us the search on the next call. */ @@ -3203,7 +3203,7 @@ void __putback_isolated_page(struct page *page, unsig= ned int order, int mt) struct zone *zone =3D page_zone(page); =20 /* zone lock should be held when this function is called */ - lockdep_assert_held(&zone->lock); + lockdep_assert_held(&zone->_lock); =20 /* Return isolated page to tail of freelist. */ __free_one_page(page, page_to_pfn(page), zone, order, mt, @@ -7086,7 +7086,7 @@ int alloc_contig_frozen_range_noprof(unsigned long st= art, unsigned long end, * pages. Because of this, we reserve the bigger range and * once this is done free the pages we are not interested in. * - * We don't have to hold zone->lock here because the pages are + * We don't have to hold zone->_lock here because the pages are * isolated thus they won't get removed from buddy. */ outer_start =3D find_large_buddy(start); @@ -7655,7 +7655,7 @@ void accept_page(struct page *page) return; } =20 - /* Unlocks zone->lock */ + /* Unlocks zone->_lock */ __accept_page(zone, &flags, page); } =20 @@ -7672,7 +7672,7 @@ static bool try_to_accept_memory_one(struct zone *zon= e) return false; } =20 - /* Unlocks zone->lock */ + /* Unlocks zone->_lock */ __accept_page(zone, &flags, page); =20 return true; @@ -7813,7 +7813,7 @@ struct page *alloc_frozen_pages_nolock_noprof(gfp_t g= fp_flags, int nid, unsigned =20 /* * Best effort allocation from percpu free list. - * If it's empty attempt to spin_trylock zone->lock. + * If it's empty attempt to spin_trylock zone->_lock. */ page =3D get_page_from_freelist(alloc_gfp, order, alloc_flags, &ac); =20 diff --git a/mm/page_isolation.c b/mm/page_isolation.c index 91a0836bf1b7..cf731370e7a7 100644 --- a/mm/page_isolation.c +++ b/mm/page_isolation.c @@ -212,7 +212,7 @@ static int set_migratetype_isolate(struct page *page, e= num pb_isolate_mode mode, zone_unlock_irqrestore(zone, flags); if (mode =3D=3D PB_ISOLATE_MODE_MEM_OFFLINE) { /* - * printk() with zone->lock held will likely trigger a + * printk() with zone->_lock held will likely trigger a * lockdep splat, so defer it here. */ dump_page(unmovable, "unmovable page"); @@ -553,7 +553,7 @@ void undo_isolate_page_range(unsigned long start_pfn, u= nsigned long end_pfn) /* * Test all pages in the range is free(means isolated) or not. * all pages in [start_pfn...end_pfn) must be in the same zone. - * zone->lock must be held before call this. + * zone->_lock must be held before call this. * * Returns the last tested pfn. */ diff --git a/mm/page_owner.c b/mm/page_owner.c index 8178e0be557f..54a4ba63b14f 100644 --- a/mm/page_owner.c +++ b/mm/page_owner.c @@ -799,7 +799,7 @@ static void init_pages_in_zone(struct zone *zone) continue; =20 /* - * To avoid having to grab zone->lock, be a little + * To avoid having to grab zone->_lock, be a little * careful when reading buddy page order. The only * danger is that we skip too much and potentially miss * some early allocated pages, which is better than --=20 2.47.3